Control board, air conditioner, control method, and control program

Abstract

Provided is a control board, an air conditioner, a control method, and a control program which make it possible to simplify wiring while controlling a plurality of electronic expansion valves. A control board 1 comprises: a CPU (50) that controls a plurality of electronic expansion valves (10) through a drive driver (20); the drive driver (20) that is provided in one-to-one correspondence with the CPU (50); an operation setting switch (60) that switches, according an operation setting switching signal which is output from the CPU(50), the drive driver (20) to setting of an electronic expansion valve (10) to be controlled so as to set an operation of the electronic expansion valve (10); and a switching switch (70) that switches a current path so that current flows, at a current value based on a phase advance clock signal which is output from the CPU (50), from the drive driver (20) to the electronic expansion valve (10) to be controlled.

Description

Control board, air conditioner, control method, and control program

[0001] The present disclosure relates to a control board, an air conditioner, a control method, and a control program.

[0002] In air conditioners, an expansion valve (electronic expansion valve) is used to reduce the pressure and expand a high-temperature, high-pressure liquid refrigerant that has passed through a condenser. The electronic expansion valve adjusts the flow rate and temperature of the refrigerant by electrically controlling the valve opening. Installing multiple electronic expansion valves in air conditioners is being considered. For example, Patent Document 1 discloses that a drive unit and multiple electronic expansion valves are connected via communication means and shutoff means.

[0003] JP 2011-127805 A

[0004] However, in the invention of Patent Document 1, when the control drive unit is a control board, the number of wires connected to the control unit increases due to the presence of multiple electronic expansion valves, and this increases the number of wires required for each device, particularly for devices that require driving or control from a control unit such as electronic expansion valves.

[0005] The present disclosure has been made in consideration of the above circumstances, and aims to provide a control board, an air conditioner, a control method, and a control program that can control multiple electronic expansion valves while simplifying wiring.

[0006] In order to solve the above problems, the control board, air conditioner, control method, and control program of the present disclosure employ the following means: The control board of the present disclosure includes a CPU that controls a plurality of electronic expansion valves via a drive driver, the drive driver provided in a one-to-one correspondence with the CPU, an operation setting switch that switches the drive driver to a setting of the electronic expansion valve to be controlled in accordance with an operation setting switching signal output from the CPU so as to perform operation setting for the electronic expansion valve, and a changeover switch that switches a current path so that current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on the phase-advancing clock signal output from the CPU.

[0007] The control board of the present disclosure includes a CPU that controls a plurality of electronic expansion valves via a drive driver, a drive driver that is provided one-to-one with the CPU and configured to set the operation of the electronic expansion valve to be controlled via SPI communication from the CPU, and a changeover switch that switches the current path so that current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on an advanced phase clock signal output from the CPU.

[0008] The air conditioner of the present disclosure includes a compressor, a condenser, an electronic expansion valve controlled by the control board, and an evaporator.

[0009] The control method disclosed herein comprises the steps of controlling a plurality of electronic expansion valves via a drive driver, switching the drive driver to the setting of the electronic expansion valve to be controlled in accordance with an operation setting switching signal output from a CPU so as to perform operation settings for the electronic expansion valve, and switching the current path so that current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on the advanced phase clock signal output from the CPU, and is executed by a computer.

[0010] The control program of the present disclosure causes a computer to execute the above-described control method.

[0011] According to the present disclosure, the components required to control a plurality of electronic expansion valves can be mounted on a control board, and the wiring of the control board can be simplified.

[0012] FIG. 1 is a diagram showing an example of a system diagram of a system inside an air conditioner as a conventional example. FIG. 2 is a diagram showing an example of wiring on a control board as a conventional example. FIG. 3 is a diagram showing a drive / control circuit on a control board as a conventional example. FIG. 4 is a diagram showing initialization of an electronic expansion valve as a conventional example. FIG. 5 is a diagram showing a control board according to some embodiments of the present disclosure. FIG. 6 is a diagram showing an example of a hardware configuration of a control device according to some embodiments of the present disclosure. FIG. 7 is a diagram showing an example of an overall control flow of a control board according to some embodiments of the present disclosure. FIG. 8 is a diagram showing details of the overall control flow of a control board according to some embodiments of the present disclosure. FIG. 9 is a diagram showing a control board according to some embodiments of the present disclosure. FIG. 10 is a diagram showing a control board according to some embodiments of the present disclosure. FIG. 11 is a diagram showing an example of an overall control flow of a control board according to some embodiments of the present disclosure. FIG. 12 is a diagram showing details of the overall control flow of a control board according to some embodiments of the present disclosure.

[0013] Hereinafter, an embodiment of a control board, an air conditioner, a control method, and a control program according to the present disclosure will be described with reference to the drawings.

[0014] Fig. 1 is a diagram showing an example of a system diagram for a conventional air conditioner. As shown in Fig. 1, an ECU (Electric Control Unit) (CPU) 90, which controls the air conditioner, and an HVAC ECU (Heating, Ventilation, and Air Conditioning Electric Control Unit) 100 are connected by cables. An electric compressor 520, a water pump 530, four pressure sensors 540, eleven temperature sensors 550, six electronic expansion valves 10, and four solenoid valves 560 are connected to the ECU 90 by cables. Each of the pressure sensor 540, the temperature sensor 550, the electronic expansion valve (expansion valve) 10, and the solenoid valve 560 requires one or more cables, and the number of wires increases in proportion to the number of devices.

[0015] The air conditioner includes a refrigerant circuit having a compressor (not shown) that compresses a refrigerant, a condenser (not shown) that condenses the compressed refrigerant, an expansion valve (not shown) that expands the condensed refrigerant, and an evaporator (not shown) that evaporates the expanded refrigerant. The refrigerant evaporated by the evaporator becomes gaseous and returns to the compressor. The air conditioner adjusts the temperature of the space to be conditioned by using the refrigerant circuit through which the refrigerant circulates. Other components of the air conditioner are not described in detail here, as known components can be used.

[0016] Fig. 2 is a diagram showing an example of wiring in a control board as a conventional example. As shown in Fig. 2, six electronic expansion valves 10a, 10b, 10c, 10d, 10e, and 10f are connected to a CPU 50. Drivers 20 (20a, 20b, 20c, 20d, 20e, and 20f) are connected between the CPU 50 and the electronic expansion valves 10. In the following description, when the electronic expansion valves 10a, 10b, 10c, 10d, 10e, and 10f are to be distinguished from one another, any of the letters a to f will be added to the end of the reference numerals, and when the electronic expansion valves 10a, 10b, 10c, 10d, 10e, and 10f are not to be distinguished from one another, the letters a to f will be omitted. Similarly, when the drivers 20a, 20b, 20c, 20d, 20e, and 20f are to be distinguished from one another, any of the letters a to f is added to the end of the reference numeral, and when the drivers 20a, 20b, 20c, 20d, 20e, and 20f are not to be distinguished from one another, the letters a to f are omitted. Similarly, when the drivers 20a, 20b, 20c, 20d, 20e, and 20f are not to be distinguished from one another, the letters a to f are omitted.

[0017] 2, when multiple electronic expansion valves 10 are connected to the CPU 50, one drive / control circuit (driver 20 and wiring) is required for each electronic expansion valve 10 in order to drive and control the electronic expansion valves 10. The cost of the driver 20 is high, and adding an additional electronic expansion valve 10 significantly increases the cost. The number of wirings outside the board also increases, making it difficult to route the wiring.

[0018] The increase in the number of drive and control circuits requires the addition of various components and wiring, and the increase in connector pins also requires the enlargement of the connector 80. This increases the size of the control board 1 and the case that houses the control board 1. In particular, when the control board 1 is mounted on a vehicle, it must be placed within a limited space, and the increase in size makes it difficult to properly place it.

[0019] The increased wiring outside the board increases noise generation and reduces noise resistance in the wiring between the driver 20 and the connector 80, and between the connector 80 and the electronic expansion valve 10. This reduces EMC (Electro Magnetic Compatibility) performance and may cause malfunctions in the entire system.

[0020] The driver 20 is a heat source and therefore requires appropriate thermal design. As the number of driver 20 increases, the number of heat sources also increases, making more detailed thermal design necessary. When there are a large number of driver 20, such as six, as shown in Figure 2, there is a risk that the control board 1 and various components may overheat.

[0021] 3 is a diagram showing a drive and control circuit on a control board as a conventional example. In FIG. 3, the electronic expansion valve 10 is shown as two electronic expansion valves 10a and 10b, but the same configuration is also shown for two or more electronic expansion valves.

[0022] The circuit that drives and controls the electronic expansion valve 10 is a circuit that performs constant current control on the electronic expansion valve 10. Operation settings for the electronic expansion valve 10 are input to MODE0, MODE1, MODE2, RSA, RSB, VREF, and CW / CCW of the drive driver 20. An operation signal for the electronic expansion valve 10 is input to CLK of the drive driver 20. Monitoring of abnormalities and the electrical angle of the electronic expansion valve 10 is performed via DIAG and MO of the drive driver 20.

[0023] In the operation setting for the electronic expansion valve 10, MODE0, MODE1, and MODE2 are used to set the excitation mode. The excitation mode is set by combining signals to each terminal. Examples of excitation modes include 1-2 phase excitation and 2-phase excitation. For the electronic expansion valve 10a in FIG. 3, 1-2 phase excitation is used, and the signal to MODE0 is set to Hi, and the signals to MODE1 and MODE2 are set to Lo. For the electronic expansion valve 10b in FIG. 3, 2-phase excitation is used, and the signals to MODE0 and MODE1 are set to Lo, and the signal to MODE2 is set to Hi. RSA and RSB are used to set the overcurrent detection value. VREF is used to set the output current value. For CW / CCW, the motor rotation direction of the electronic expansion valve 10 is set by the CPU 50 (motor rotation direction setting). The operation settings for the electronic expansion valve 10 are made by setting the excitation mode, output current, and current detection using input signals to the drive driver 20, and each mode and output current value is appropriately set depending on the electronic expansion valve 10 to be controlled.

[0024] In the operation signal for the electronic expansion valve 10, the CLK is set as an advanced clock signal by the CPU 50. When the advanced clock signal is input to the driver 20, the electronic expansion valve 10 is controlled in accordance with the setting.

[0025] In monitoring the abnormality and electrical angle of the electronic expansion valve 10, the driver 20 holds information on the electronic expansion valve 10 that is currently being controlled. The held information includes abnormalities in the electronic expansion valve 10 and the electrical angle of the electronic expansion valve 10. In monitoring the abnormality and electrical angle of the electronic expansion valve 10, the DIAG outputs an abnormality detection to the CPU 50. The MO outputs the monitoring result of the electrical angle of each electronic expansion valve 10 (electrical angle monitor) to the CPU 50.

[0026] The drive driver 20 controls the electronic expansion valve 10 by passing current through OUTA+, OUTA-, OUTB+, and OUTB- to the electronic expansion valve 10. OUTA+ is connected to one side of the coil of the motor of the electronic expansion valve 10, OUTA- is connected to the other side of the coil of the motor of the electronic expansion valve 10, OUTB+ is connected to one side of the coil different from OUTA of the motor of the electronic expansion valve 10, and OUTB- is connected to the other side of the coil different from OUTA of the motor of the electronic expansion valve 10. The direction of the current between OUTA+ and OUTA- and the direction of the current between OUTB+ and OUTB- are changed by switching a switch (not shown) inside the drive driver 20.

[0027] In this way, the CPU 50 requires multiple CPU ports for each electronic expansion valve 10, i.e., for each driver 20, so as the number of electronic expansion valves 10 to be controlled increases, the number of required ports also increases proportionally. If the number of required CPU ports increases, the ports of the CPU 50 may become insufficient, which may result in the need to change the CPU 50. The wiring on the control board 1 becomes complicated, making board design difficult.

[0028] A resistor 41 is connected to RSA, and a resistor 42 is connected to RSB. RSA senses the voltage across resistor 41, and RSB senses the voltage across resistor 42. Resistors 43 and 44 are connected to VREF. VREF senses the voltage division value. In the drive and control circuit of the electronic expansion valve 10, the constant current value and the overcurrent value are set by resistors 41, 42, 43, and 44 connected to the terminals RSA, RSB, and VREF, respectively. Therefore, when changing each set value, it is necessary to change the resistance values. Resistors 41, 42, 43, and 44 are fixed resistors, and changing the resistance values ​​requires changing the constants, which results in a major design change.

[0029] 4A and 4B are diagrams showing initialization of a conventional electronic expansion valve, in which Fig. 4A shows initialization when the valve opening of the electronic expansion valve 10 is changed from fully open to fully closed, and Fig. 4B shows initialization when the valve opening of the electronic expansion valve 10 is changed from low to fully closed.

[0030] Initialization of the electronic expansion valve 10 involves closing the valve from the stop position in the previous drive to the fully closed position. In initialization, in addition to the tightening required to move from fully open to fully closed, retightening is also performed to ensure that the valve is reliably in the fully closed position. The retightening is an operation to close the valve further in the direction that closes the valve from the fully closed position.

[0031] 4A, the distance in the valve closing direction from the fully open position to the fully closed position is c1. For additional tightening, a closing operation is performed in the valve closing direction by a distance d1.

[0032] In Figure 4(b), the distance in the valve closing direction from the position where the electronic expansion valve 10 is at a low opening (closer to fully closed than fully open) to the fully closed position is c2, which is shorter than c1. As a retightening operation, a closing operation of a distance d2 is performed in the valve closing direction. Since the distance d2 is longer than d1, when initialization is performed with the electronic expansion valve 10 at a low opening, retightening occurs frequently. Because extra force is applied to the parts pressed down by the retightening, the life of the electronic expansion valve 10 is shortened.

[0033] In this way, increasing the number of electronic expansion valves 10 in a conventional control board 1 causes various problems, but the control board 1 of the present disclosure solves these problems.

[0034] First Embodiment A first embodiment of the present disclosure will be described below with reference to Fig. 5. Fig. 5 is a diagram showing a control board in several embodiments of the present disclosure. As shown in Fig. 5, the control board 1 includes a CPU 50, an operation setting switch 60, a driver 20, a selector switch 70, a connector 80, and electronic expansion valves (expansion valves) 10 (10a and 10b). This embodiment differs from conventional examples in that it includes the operation setting switch 60 and the selector switch 70, and in that even when multiple electronic expansion valves 10 are connected, only one driver 20 is provided, and there is a one-to-one correspondence between the CPU 50 and the driver 20.

[0035] 6 is a diagram showing an example of a hardware configuration of a CPU in some embodiments of the present disclosure. As shown in FIG. 6, the CPU 50 is a computer (calculating machine) and includes, for example, a CPU (Central Processing Unit: processor) 1100, a secondary storage device (ROM, Secondary storage: memory) 1300, a main storage device (RAM, Main Memory) 1200, a communication I / F 1400 for connecting to a network or the like, and an input / output unit 1500. These units are connected via a bus 1800.

[0036] The CPU 1100 controls the entire CPU 50 using, for example, an operating system (OS) stored in a secondary storage device 1300 connected via a bus 1800, and executes various processes by executing various programs stored in the secondary storage device 1300. One or more CPUs 1100 may be provided, and they may cooperate with each other to realize processes.

[0037] The main memory device 1200 is composed of writable memory such as cache memory or RAM (Random Access Memory), and is used as a working area for reading out programs executed by the CPU 1100 and writing data processed by the programs.

[0038] The secondary storage device 1300 is a non-transitory computer-readable storage medium. The secondary storage device 1300 is, for example, a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, or a semiconductor memory. Examples of the secondary storage device 1300 include a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), and a flash memory. The secondary storage device 1300 stores, for example, an OS for controlling the entire information processing device, such as Windows (registered trademark), iOS (registered trademark), or Android (registered trademark), a BIOS (Basic Input / Output System), various device drivers for operating peripheral devices, various application software, and various data and files. The secondary storage device 1300 also stores programs for implementing various processes and various data required for implementing the various processes. A plurality of secondary storage devices 1300 may be provided, and the above-mentioned programs and data may be stored separately in each secondary storage device 1300.

[0039] A series of processes for realizing the functions of the CPU 50 is stored in the secondary storage device 1300 or the like in the form of a program, and the CPU (processor) 1100 reads this program into the main storage device 1200 and executes information processing and arithmetic processing to realize various functions. Note that the program may be pre-installed in the secondary storage device 1300, provided in a state stored in another non-transitory computer-readable storage medium, or distributed via wired or wireless communication means. Examples of non-transitory computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories.

[0040] As shown in FIG. 5 , an operation setting switch 60 is provided between the CPU 50 and the driver 20. The operation setting switch 60 switches the driver 20 to the setting of the electronic expansion valve 10 to be controlled in response to an operation setting switching signal output from the CPU 50. The operation setting switch 60 is, for example, a multiplexer, a transistor, or the like. A changeover switch 70 is provided between the driver 20 and the connector 80 and electronic expansion valve 10. The changeover switch 70 switches the current path so that current flows from the driver 20 to the electronic expansion valve 10 to be controlled at a current value based on the phase-advancing clock signal output from the CPU 50. The changeover switch 70 switches the current path in response to the motor current path switching signal output from the CPU 50. The changeover switch 70 is, for example, a bidirectional semiconductor switch, such as a solid-state relay. Dummy loads 31 and 32, such as coils and resistors, may be provided between the changeover switch 70 and the connector 80 and electronic expansion valve 10. Although FIG. 5 shows a case where the electronic expansion valve 10 includes two electronic expansion valves 10a and 10b, a similar configuration is also shown for a case where there are two or more electronic expansion valves.

[0041] Operation settings for the electronic expansion valve 10 are input to MODE0, MODE1, MODE2, RSA, RSB, VREF, and CW / CCW of the driver 20. An operation signal for the electronic expansion valve 10 is input to CLK of the driver 20. Monitoring of abnormalities and the electrical angle of the electronic expansion valve 10 is performed via DIAG and MO of the driver 20.

[0042] In the operation settings for the electronic expansion valve 10, MODE0, MODE1, and MODE2, which set the excitation mode, RSA and RSB, which set the overcurrent detection value, and VREF, which set the output current value, are input as input signals from the operation setting switch 60. The input signals from the operation setting switch 60 are set based on an operation setting switching signal from the CPU 50. The motor rotation direction (CW / CCW) of the electronic expansion valve 10 is set by the CPU 50 (motor rotation direction setting). In this way, the operation settings for the electronic expansion valve 10 are set by input signals to the drive driver 20 via the operation setting switch 60 to set the excitation mode, output current, and current detection, and each mode and output current value is appropriately set depending on the electronic expansion valve 10 to be controlled. The motor rotation direction setting is input directly from the CPU 50 to the drive driver 20.

[0043] In the operation signal for the electronic expansion valve 10, the CLK is set as an advanced clock signal by the CPU 50. When the advanced clock signal is input to the driver 20, the electronic expansion valve 10 is controlled in accordance with the setting.

[0044] In monitoring the abnormality and electrical angle of the electronic expansion valve 10, the driver 20 holds information on the electronic expansion valve 10 that is currently being controlled. The held information includes abnormalities in the electronic expansion valve 10 and the electrical angle of the electronic expansion valve 10. In monitoring the abnormality and electrical angle of the electronic expansion valve 10, the DIAG outputs an abnormality detection to the CPU 50. The MO outputs the monitoring result of the electrical angle of each electronic expansion valve 10 (electrical angle monitor) to the CPU 50.

[0045] The drive driver 20 controls the electronic expansion valve 10 by passing current through OUTA+, OUTA-, OUTB+, and OUTB- to the electronic expansion valve 10. OUTA+ is connected to one side of the coil of the motor of the electronic expansion valve 10, OUTA- is connected to the other side of the coil of the motor of the electronic expansion valve 10, OUTB+ is connected to one side of the coil different from OUTA of the motor of the electronic expansion valve 10, and OUTB- is connected to the other side of the coil different from OUTA of the motor of the electronic expansion valve 10. The direction of the current between OUTA+ and OUTA- and the direction of the current between OUTB+ and OUTB- are changed by switching a switch (not shown) inside the drive driver 20.

[0046] A changeover switch 70 is connected to the driver 20 of the embodiment of the present disclosure, and the changeover switch 70 switches the current path so that current flows from the driver 20 to the electronic expansion valve 10 to be controlled. By providing the changeover switch 70, it is not necessary to provide multiple driver drivers 20 even if there are multiple electronic expansion valves 10.

[0047] In an embodiment of the present disclosure, the operation settings and operation signals for each electronic expansion valve 10 are sequentially set for each electronic expansion valve 10. When switching the electronic expansion valve 10 to be controlled, the electrical angle corresponding to the position (valve opening) of the electronic expansion valve 10 immediately before the switching is stored. When control of the same electronic expansion valve 10 is resumed, control must be performed from the same electrical angle. However, the driver 20 does not have a storage configuration. In an embodiment of the present disclosure, the CPU 50 stores the position (stop position) immediately before the switching (when stopped). When control of the same electronic expansion valve 10 is resumed, a current value based on the advanced phase clock signal output from the CPU 50 is passed from the driver 20 to the load 31 or 32, rather than to the electronic expansion valve 10, and the electrical angle of the driver 20 is increased or decreased by one step. The selector switch 70 switches the switch so that current flows to the load 31 or 32. The electrical angle of the electronic expansion valve 10 to be controlled, which is stored in the CPU 50, is called by the CPU 50, and processing is performed until the electrical angle of the driver 20 becomes the same as the stored electrical angle of the electronic expansion valve 10 to be controlled. In this way, the electrical angle of the driver 20 is adjusted to the stop position (electrical angle) of the electronic expansion valve 10 to be controlled, and control can be continued.

[0048] It is also possible to eliminate the loads 31 and 32 and the two switches for passing current to the loads 31 and 32. If the loads 31 and 32 and the two switches are not provided, the positions (stop positions) of all the electronic expansion valves 10 immediately before switching (when stopped) may be the same for all the electronic expansion valves 10. By making the electrical angles of all the electronic expansion valves 10 when stopped the same, the driver 20 may perform control from the same electrical angle when switching the electronic expansion valves 10 to be controlled.

[0049] Fig. 7 is a diagram showing an example of the overall control flow of the control board in some embodiments of the present disclosure. Figs. 8 to 10 are diagrams showing details of the overall control flow of the control board in some embodiments of the present disclosure. In the embodiment of the present disclosure, a control flow for two electronic expansion valves 10a and 10b is described, but even if there are three or more electronic expansion valves 10, control is possible by performing the same processing on each electronic expansion valve 10.

[0050] 7, power is turned on to operate the control board 1. In step S120, all electronic expansion valves 10 are initialized.

[0051] Fig. 8 shows details of step S120 in Fig. 7. In step S121 in Fig. 8, the CPU 50 switches the operation setting switch 60 and the changeover switch 70 so that they correspond to the electronic expansion valve 10a. Since the operation setting switch 60 is switched so that it corresponds to the electronic expansion valve 10a, the driver 20 is set so that it corresponds to the electronic expansion valve 10a. Since the changeover switch 70 is switched so that it corresponds to the electronic expansion valve 10a, each switch is turned ON / OFF to switch the current path so that OUTA+, OUTB+, OUTA-, and OUTB- of the driver 20 are connected to the electronic expansion valve 10a, respectively. As a result, current flows from the driver 20 to the electronic expansion valve 10a.

[0052] In step S122, the CPU 50 transmits a phase-advancing clock signal corresponding to the electronic expansion valve 10a to the driver 20, and the driver 20 passes a current of a corresponding current value through the electronic expansion valve 10a.

[0053] In step S123, it is determined whether the required number of pulses has been transmitted to the electronic expansion valve 10a and whether current has flowed up to the required number of pulses. If it is determined that the required number of pulses has been transmitted (transmitted) (Y in S123), the process proceeds to step S124. On the other hand, if it is determined that the required number of pulses has not been transmitted (N in S123), the process returns to step S122. The required number of pulses is the number of pulses required to move the electronic expansion valve 10a from fully open to fully closed, plus the number of pulses required for the aforementioned retightening.

[0054] If it is determined that the required number of pulses have been transmitted to the electronic expansion valve 10a, the process proceeds to step S124, where the CPU 50 switches the operation setting switch 60 and the changeover switch 70 so that they correspond to the next electronic expansion valve 10b. Since the operation setting switch 60 is switched so that it corresponds to the electronic expansion valve 10b, the drive driver 20 is set so that it corresponds to the electronic expansion valve 10b. Since the changeover switch 70 is switched so that it corresponds to the electronic expansion valve 10b, each switch is turned ON / OFF to switch the current path so that OUTA+, OUTB+, OUTA-, and OUTB- of the drive driver 20 are connected to the electronic expansion valve 10b, respectively. As a result, current flows from the drive driver 20 to the electronic expansion valve 10b.

[0055] In step S125, the CPU 50 transmits a phase-advancing clock signal corresponding to the electronic expansion valve 10b to the driver 20, and the driver 20 passes a current at a current value corresponding to the electronic expansion valve 10b.

[0056] In step S126, it is determined whether the required number of pulses has been transmitted to the electronic expansion valve 10b. If it is determined that the required number of pulses has been transmitted (transmitted) (Y in S126), the process proceeds to step S130. On the other hand, if it is determined that the required number of pulses has not been transmitted (N in S126), the process returns to step S125. In this manner, each electronic expansion valve 10 is initialized, and each electronic expansion valve 10 is tightened to the fully closed position, including retightening. When three or more electronic expansion valves 10 are installed, all electronic expansion valves 10 are initialized in the same manner.

[0057] 7, the operation setting switch 60 and the changeover switch 70 are switched. In step S140, the dummy load is energized. FIG. 9 shows the details of steps S130 and S140 in FIG.

[0058] In step S130 of FIG. 9 , the CPU 50 switches the operation setting switch 60 and the selector switch 70 to correspond to the electrical angle adjustment of the electronic expansion valve 10a. The control of each electronic expansion valve 10 by the CPU 50 via the driver 20 is performed sequentially for each electronic expansion valve 10. For example, if the electronic expansion valve 10a is controlled, then the electronic expansion valve 10b is controlled, and then the electronic expansion valve 10a is controlled again, the re-control of the electronic expansion valve 10a must start from the electrical angle of the electronic expansion valve 10a when it was previously stopped. However, the driver 20 cannot store the electrical angle of each electronic expansion valve 10 when it was stopped. The electrical angle of each electronic expansion valve 10 when it was stopped must be stored by the CPU 50. In order to re-control each electronic expansion valve 10 from the electrical angle stored by the CPU 50, a process is performed to advance (or return) the desired electrical angle using the loads (dummy loads) 31 and 32. To adjust the electrical angle, the changeover switch 70 switches the current path by turning on / off each switch to connect to the loads 31 and 32. This causes current to flow from the driver 20 to the loads 31 and 32.

[0059] In step S141, the CPU 50 retrieves the information recorded one step before regarding the electrical angle of the electronic expansion valve 10 a. For example, if the electrical angle of the electronic expansion valve 10 a one step before is 90 degrees, the electrical angle of 90 degrees is retrieved.

[0060] In step S142, the CPU 50 transmits a phase-advancing clock signal to cause current to flow through the loads 31 and 32. The CPU 50 transmits a phase-advancing clock signal to cause current to flow through the loads 31 and 32, and adds, for example, 30 degrees to the driver-side electrical angle, which is the electrical angle of the driver 20 (increase the electrical angle by one step), so that the electrical angle of the driver 20 (electronic expansion valve 10a) matches the electrical angle of the CPU 50. The reason why current is caused to flow through the loads 31 and 32 is because the driver 20 cannot advance the electrical angle without current flow.

[0061] In step S143, it is determined whether the CPU-side electrical angle, which is the electrical angle of the CPU 50, is equal to the driver-side electrical angle. If it is determined that the CPU-side electrical angle is equal to the driver-side electrical angle (Y in S143), the process proceeds to step S150. On the other hand, if it is determined that the CPU-side electrical angle is not equal to the driver-side electrical angle (N in S143), the process returns to step S142, where an additional 30 degrees is added to the driver-side electrical angle. For example, if the electrical angle of the electronic expansion valve 10a is 3, the CPU-side electrical angle is 90 degrees, and therefore the driver-side electrical angle is added until the driver-side electrical angle reaches 90 degrees. If subtraction approaches the desired electrical angle more quickly than addition, 30 degrees may be subtracted (the electrical angle is reduced by one step).

[0062] 7, the operation setting switch 60 and the changeover switch 70 are switched. In step S160, the electronic expansion valve 10a is driven. FIG. 10 shows the details of steps S150 and S160 in FIG.

[0063] 10, the CPU 50 switches the operation setting switch 60 and the changeover switch 70 so that they correspond to the driving of the electronic expansion valve 10a. Since the operation setting switch 60 is switched so that it corresponds to the electronic expansion valve 10a, the drive driver 20 is set so that it corresponds to the electronic expansion valve 10a. Furthermore, since the changeover switch 70 is switched so that it corresponds to the electronic expansion valve 10a, each switch is turned ON / OFF to switch the current path so that OUTA+, OUTB+, OUTA-, and OUTB- of the drive driver 20 are connected to the electronic expansion valve 10a. As a result, current flows from the drive driver 20 to the electronic expansion valve 10a.

[0064] In step S161, the CPU 50 transmits a phase-advancing clock signal to cause a current to flow through the electronic expansion valve 10 a. In order to control the electronic expansion valve 10 a according to the settings, the CPU 50 transmits the phase-advancing clock signal to cause a current to flow through the electronic expansion valve 10 a, and adds, for example, 30 degrees to the driver-side electrical angle, which is the electrical angle of the drive driver 20 (increasing the electrical angle by one step).

[0065] In step S162, the CPU 50 determines whether or not the required number of pulses has been transmitted to the driver 20 (transmission completed). The required number of pulses is the number of pulses corresponding to the driver-side electrical angle according to the control settings of the electronic expansion valve 10a. If it is determined that the CPU 50 has transmitted the required number of pulses to the driver 20 (Y in S162), the process proceeds to step S163. On the other hand, if it is determined that the CPU 50 has not transmitted the required number of pulses to the driver 20 (N in S162), the process returns to step S161, where an additional 30 degrees is added to the driver-side electrical angle. For example, if the set value of the electrical angle of the electronic expansion valve 10a is 240 degrees, the driver-side electrical angle is added until the driver-side electrical angle reaches 240 degrees, and current is passed through the electronic expansion valve 10a.

[0066] In step S163, the CPU 50 updates the recorded information regarding the electrical angle of the electronic expansion valve 10a. The CPU 50 stores the electrical angle when the electronic expansion valve 10a is stopped until the next step in which the electronic expansion valve 10a is controlled.

[0067] Control related to the electronic expansion valve 10b is performed in steps S170 to S200 in Fig. 7. In step S170 in Fig. 7, the operation setting switch 60 and the changeover switch 70 are switched. In step S180, current is passed through the dummy load. In step S190, the operation setting switch 60 and the changeover switch 70 are switched. In step S200, the electronic expansion valve 10b is driven. Control similar to that for the electronic expansion valve 10a is performed for the electronic expansion valve 10b. When control of the electronic expansion valve 10b is completed, the control target is rotated, and control is again performed for the electronic expansion valve 10a. When three or more electronic expansion valves 10 are installed, control of all of the electronic expansion valves 10 is performed sequentially in the same manner.

[0068] [Modifications] In the present embodiment, the negative poles of the electronic expansion valves 10 for each phase are shared outside the control board 1, but the positive poles may also be shared. Hereinafter, the control board, air conditioner, control method, and control program of the modification will be described, focusing on the differences and omitting the description of the commonalities with the first embodiment. FIG. 11 is a diagram showing a control board in some embodiments of the present disclosure. As shown in FIG. 11, the control board 1 includes a CPU 50, an operation setting switch 60, a driver 20, a selector switch 70, a connector 80, and electronic expansion valves (expansion valves) 10 (10a and 10b).

[0069] In this modification, wiring is performed outside the control board 1, i.e., between the connector 80 and each electronic expansion valve 10, to share the positive pole side of each phase. As with the case where the negative pole side is shared outside the board, this modification can reduce the number of input lines (wiring) to the control board 1, and can make the connector 80 of the control board 1 smaller.

[0070] Second Embodiment A second embodiment of the present disclosure will be described below with reference to FIG. 12 . In the first embodiment, the positive or negative electrode of each phase of the electronic expansion valve 10 is shared outside the control board 1. However, this embodiment differs from the first embodiment in that the positive or negative electrode of each phase of the electronic expansion valve 10 is shared within the control board 1. In this embodiment, an example in which the negative electrode of each phase is shared within the board will be described. Below, with regard to the control board, air conditioner, control method, and control program of several embodiments of the present disclosure, a description of the points in common with the first embodiment will be omitted, and differences will be mainly described.

[0071] 12 is a diagram showing a control board according to some embodiments of the present disclosure. As shown in FIG. 12, the control board 1 includes a CPU 50, an operation setting switch 60, a driver 20, a selector switch 70, a connector 80, and electronic expansion valves (expansion valves) 10 (10a and 10b).

[0072] In this embodiment, wiring is performed so that the negative poles of each phase are shared between the changeover switch 70 and the connector 80. Although the number of input lines to the control board 1 is increased compared to the first embodiment, the number of lines outside the control board 1 is reduced, and therefore, in this embodiment, noise resistance is improved and noise generation is reduced.

[0073] Third Embodiment A third embodiment of the present disclosure will be described below with reference to Fig. 13. In the first embodiment, the operation setting switch 60 was used to set the operation of the drive driver 20, but this embodiment differs from the first embodiment in that the operation setting is performed using SPI communication (Serial Peripheral Interface communication). Below, with regard to the control board, air conditioner, control method, and control program in several embodiments of the present disclosure, a description of the points in common with the first embodiment will be omitted, and differences will be mainly described.

[0074] 13 is a diagram showing a control board according to some embodiments of the present disclosure. As shown in FIG. 13, the control board 1 includes a CPU 50, a driver 20, a selector switch 70, a connector 80, and electronic expansion valves (expansion valves) 10 (10a and 10b).

[0075] As shown in Fig. 13, SPI communication is performed between the CPU 50 and the driver 20. The driver 20 switches the setting of the electronic expansion valve 10 to be controlled so as to set the operation of the electronic expansion valve 10 to be controlled in accordance with the output from the CPU 50. Fig. 13 shows a case where there are two electronic expansion valves 10, electronic expansion valves 10a and 10b, but a similar configuration is also shown when there are two or more electronic expansion valves.

[0076] Operation settings for the electronic expansion valve 10 are input by SPI communication to CSB, SCK, SDI, and SDO of the driver 20. Abnormality detection of the electronic expansion valve 10 is performed via DIAG of the driver 20.

[0077] The signals are CSB, which selects a subnode by chip select, SCK, which receives a clock signal, SDI, which is used to output data from the CPU 50 to the driver 20, and SDO, which is used to input data from the driver 20 to the CPU 50. Using these signals, operation settings such as phase advance, excitation mode, and rotation direction are made according to the electronic expansion valve 10 to be controlled.

[0078] Fig. 14 is a diagram showing an example of the overall control flow of the control board in some embodiments of the present disclosure. Figs. 15 to 17 are diagrams showing details of the overall control flow of the control board in some embodiments of the present disclosure. In the embodiment of the present disclosure, a control flow for two electronic expansion valves 10a and 10b is described, but even if there are three or more electronic expansion valves 10, control is possible by performing the same processing on each electronic expansion valve 10.

[0079] 14, power is turned on to operate the control board 1. In step S320, all electronic expansion valves 10 are initialized.

[0080] Fig. 15 shows details of step S320 in Fig. 14. In step S321 in Fig. 15, the CPU 50 switches the setting of the driver 20 via SPI communication so that it corresponds to the electronic expansion valve 10a. The changeover switch 70 is switched so that it corresponds to the electronic expansion valve 10a. Since the changeover switch 70 is switched so that it corresponds to the electronic expansion valve 10a, the current paths are switched by turning each switch ON / OFF so that OUTA+, OUTB+, OUTA-, and OUTB- of the driver 20 are connected to the electronic expansion valve 10a, respectively. As a result, current flows from the driver 20 to the electronic expansion valve 10a.

[0081] In step S322, the CPU 50 transmits a phase-advancing clock signal corresponding to the electronic expansion valve 10a to the driver 20 by SPI communication, and the driver 20 passes a current at a current value corresponding to the electronic expansion valve 10a.

[0082] In step S323, it is determined whether the required number of pulses has been transmitted to the electronic expansion valve 10a. If it is determined that the required number of pulses has been transmitted (transmitted) (Y in S323), the process proceeds to step S324. On the other hand, if it is determined that the required number of pulses has not been transmitted (N in S323), the process returns to step S322. The required number of pulses is the number of pulses required to move the electronic expansion valve 10a from fully open to fully closed, plus the number of pulses required for the aforementioned retightening.

[0083] If it is determined that the required number of pulses have been transmitted to the electronic expansion valve 10a, the process proceeds to step S324, where the CPU 50 switches the setting of the drive driver 20 via SPI communication so that it corresponds to the electronic expansion valve 10b. The changeover switch 70 is then switched so that it corresponds to the electronic expansion valve 10b. Since the changeover switch 70 is switched so that it corresponds to the electronic expansion valve 10b, the current paths are switched by turning each switch ON / OFF so that OUTA+, OUTB+, OUTA-, and OUTB- of the drive driver 20 are connected to the electronic expansion valve 10b, respectively. As a result, current flows from the drive driver 20 to the electronic expansion valve 10b.

[0084] In step S325, the CPU 50 transmits a phase-advancing clock signal corresponding to the electronic expansion valve 10b to the driver 20 by SPI communication, and the driver 20 passes a current at a current value corresponding to the electronic expansion valve 10b.

[0085] In step S326, it is determined whether the required number of pulses has been transmitted to the electronic expansion valve 10b. If it is determined that the required number of pulses has been transmitted (transmitted) (Y in S326), the process proceeds to step S330. On the other hand, if it is determined that the required number of pulses has not been transmitted (N in S326), the process returns to step S325. Each electronic expansion valve 10 is initialized, and each electronic expansion valve 10 is tightened to the fully closed position, including retightening. If three or more electronic expansion valves 10 are installed, all electronic expansion valves 10 are initialized in the same manner.

[0086] In step S330 of Fig. 14, the setting is changed over by SPI communication and the changeover switch 70 is changed over. In step S340, current is applied to the dummy load. Fig. 16 shows the details of steps S330 and S340 of Fig. 14.

[0087] In step S330 of FIG. 16 , the CPU 50 switches the setting of the drive driver 20 via SPI communication to correspond to the electrical angle adjustment of the electronic expansion valve 10a. The selector switch 70 is switched to correspond to the electrical angle adjustment of the electronic expansion valve 10a. The control of each electronic expansion valve 10 by the CPU 50 via the drive driver 20 is performed sequentially for each electronic expansion valve 10. For example, if the electronic expansion valve 10a is controlled, then the electronic expansion valve 10b is controlled, and then the electronic expansion valve 10a is controlled again, the re-control of the electronic expansion valve 10a must start from the electrical angle of the electronic expansion valve 10a when it was last stopped. However, the drive driver 20 cannot store the electrical angle of each electronic expansion valve 10 when it was stopped. The electrical angle of each electronic expansion valve 10 when it was stopped must be stored by the CPU 50. In order to re-control each electronic expansion valve 10 from the electrical angle stored by the CPU 50, a process is performed to advance (or return) the desired electrical angle using the loads (dummy loads) 31 and 32. To adjust the electrical angle, the changeover switch 70 switches the current path by turning on / off each switch to connect to the loads 31 and 32. This causes current to flow from the driver 20 to the loads 31 and 32.

[0088] In step S341, the CPU 50 retrieves the information recorded one step before regarding the electrical angle of the electronic expansion valve 10a. For example, it is assumed that the electrical angle of the electronic expansion valve 10a one step before was 90 degrees.

[0089] In step S342, the CPU 50 transmits a phase-advancing clock signal via SPI communication to cause current to flow through the loads 31 and 32. The CPU 50 transmits the phase-advancing clock signal to cause current to flow through the loads 31 and 32 so that the electrical angle of the drive driver 20 (electronic expansion valve 10a) matches the electrical angle of the CPU 50, and adds 30 degrees to the driver-side electrical angle, which is the electrical angle of the drive driver 20 (increases the electrical angle by one step).

[0090] In step S343, it is determined whether the CPU-side electrical angle, which is the electrical angle of the CPU 50, is equal to the driver-side electrical angle. If it is determined that the CPU-side electrical angle is equal to the driver-side electrical angle (Y in S343), the process proceeds to step S350. On the other hand, if it is determined that the CPU-side electrical angle is not equal to the driver-side electrical angle (N in S343), the process returns to step S342, where an additional 30 degrees is added to the driver-side electrical angle. For example, if the electrical angle of the electronic expansion valve 10a is 90 degrees, the CPU-side electrical angle is also 90 degrees, and therefore the driver-side electrical angle is added until the driver-side electrical angle reaches 90 degrees.

[0091] In step S350 of Fig. 14, the setting is changed by SPI communication and the changeover switch 70 is changed. In step S360, the electronic expansion valve 10a is driven. Fig. 17 shows the details of steps S350 and S360 of Fig. 14.

[0092] 17, the CPU 50 uses SPI communication to change the settings of the driver 20 to correspond to the driving of the electronic expansion valve 10a. The changeover switch 70 is changed over to correspond to the driving of the electronic expansion valve 10a. Since the changeover switch 70 is changed over to correspond to the electronic expansion valve 10a, the current paths are changed over by turning each switch ON / OFF so that OUTA+, OUTB+, OUTA-, and OUTB- of the driver 20 are connected to the electronic expansion valve 10a. As a result, current flows from the driver 20 to the electronic expansion valve 10a.

[0093] In step S361, the CPU 50 transmits a phase-advancing clock signal via SPI communication to cause a current to flow through the electronic expansion valve 10 a. In order to control the electronic expansion valve 10 a according to the settings, the CPU 50 transmits the phase-advancing clock signal to cause a current to flow through the electronic expansion valve 10 a and adds 30 degrees to the driver-side electrical angle, which is the electrical angle of the drive driver 20 (increases the electrical angle by one step).

[0094] In step S362, the CPU 50 determines whether or not the required number of pulses has been transmitted to the driver 20 (transmission completed). The required number of pulses is the number of pulses corresponding to the driver-side electrical angle according to the control settings of the electronic expansion valve 10a. If it is determined that the CPU 50 has transmitted the required number of pulses to the driver 20 (Y in S362), the process proceeds to step S363. On the other hand, if it is determined that the CPU 50 has not transmitted the required number of pulses to the driver 20 (N in S362), the process returns to step S361, where an additional 30 degrees is added to the driver-side electrical angle. For example, if the set value of the electrical angle of the electronic expansion valve 10a is 240 degrees, the driver-side electrical angle is added until the driver-side electrical angle reaches 240 degrees, and current is passed through the electronic expansion valve 10a.

[0095] In step S363, the CPU 50 updates the recorded information regarding the electrical angle of the electronic expansion valve 10a. The CPU 50 stores the electrical angle when the electronic expansion valve 10a is stopped until the next step in which the electronic expansion valve 10a is controlled.

[0096] Control related to the electronic expansion valve 10b is performed in steps S370 to S200 in Fig. 14. In step S370 in Fig. 14, settings are switched by SPI communication, and the changeover switch 70 is switched. In step S380, current is supplied to the dummy load. In step S390, settings are switched by SPI communication, and the changeover switch 70 is switched. In step S400, the electronic expansion valve 10b is driven. Control similar to that for the electronic expansion valve 10a is performed for the electronic expansion valve 10b. When control of the electronic expansion valve 10b is completed, the control target is switched, and control is again performed for the electronic expansion valve 10a. When three or more electronic expansion valves 10 are installed, control of all of the electronic expansion valves 10 is performed sequentially in the same manner.

[0097] Fourth Embodiment A fourth embodiment of the present disclosure will be described below with reference to FIG. 18 . In the third embodiment, the positive or negative electrode of each phase of the electronic expansion valve 10 is shared outside the control board 1. However, this embodiment differs from the third embodiment in that the positive or negative electrode of each phase of the electronic expansion valve 10 is shared within the control board 1. In this embodiment, an example in which the negative electrode of each phase is shared within the board will be described. Below, with regard to the control board, air conditioner, control method, and control program of several embodiments of the present disclosure, a description of the points in common with the first embodiment will be omitted, and differences will be mainly described.

[0098] 18 is a diagram showing a control board according to some embodiments of the present disclosure. As shown in Fig. 18, the control board 1 includes a CPU 50, a driver 20, a selector switch 70, a connector 80, and electronic expansion valves (expansion valves) 10 (10a and 10b).

[0099] In this embodiment, wiring is performed so as to share the negative pole side of each phase between the changeover switch 70 and the connector 80. In this embodiment, the number of input lines to the control board 1 is increased compared to the first embodiment, but the number of lines outside the control board 1 is reduced, thereby improving noise resistance and reducing noise generation.

[0100] <Additional Notes> The control board, air conditioner, control method, and control program described in the above-described embodiments can be understood, for example, as follows.

[0101] The control board (1) of the first aspect of the present disclosure includes a CPU (50) that controls a plurality of electronic expansion valves (10) via a drive driver (20), the drive driver that is provided one-to-one with the CPU, an operation setting switch (60) that switches the drive driver to the setting of the electronic expansion valve to be controlled in accordance with an operation setting switching signal output from the CPU so as to perform operation setting for the electronic expansion valve, and a changeover switch (70) that switches the current path so that current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on the advanced phase clock signal output from the CPU.

[0102] The control board includes an operation setting switch that switches in response to an operation setting switching signal output from the CPU, and a changeover switch that switches a current path so that current flows from the drive driver to the electronic expansion valve to be controlled. This makes it possible to simplify the wiring of the control board while mounting the configuration necessary to control the multiple electronic expansion valves. For example, when adding one electronic expansion valve to the control board of the present disclosure, control is possible by simply adding two changeover switches and one CPU port of the drive driver.

[0103] In the control board of the second aspect of the present disclosure, in the first aspect, the CPU may call up the stored electrical angle of the electronic expansion valve to be controlled, the changeover switch may switch the current path so that current flows from the drive driver to the load (31, 32) at a current value based on an advanced phase clock signal output from the CPU, and the drive driver may increase or decrease the electrical angle by one step in accordance with the advanced phase clock signal until the electrical angle of the electronic expansion valve to be controlled matches the electrical angle of the drive driver.

[0104] Although the drive driver cannot store the electrical angle of the electronic expansion valve being driven, the CPU stores the electrical angle of the electronic expansion valve and can reproduce the corresponding electrical angle using a load, so that the previous control position can be restored when controlling multiple electronic expansion valves.

[0105] In the control board of the third aspect of the present disclosure, in the first or second aspect, the CPU may fix the stop position of each of the electronic expansion valves and end the control.

[0106] When the control of the electronic expansion valves is terminated, the stop positions of all the electronic expansion valves are fixed, eliminating the need to record the control positions (electrical angles). This eliminates the need to use switches and loads required for adjusting the electrical angles of the changeover switches.

[0107] The control board of a fourth aspect of the present disclosure may be configured in any one of the first to third aspects such that wiring on the positive or negative side of each phase of the electronic expansion valve is shared outside the control board.

[0108] By sharing the wiring outside the control board, the number of input lines to the control board can be reduced, and the connector 80 of the control board can be made smaller.

[0109] A control board according to a fifth aspect of the present disclosure is any one of the first to third aspects, wherein wiring on the positive or negative side of each phase of the electronic expansion valve may be shared within the control board.

[0110] By sharing the wiring within the control board, the amount of wiring outside the control board can be reduced, improving noise resistance, which prevents a deterioration in EMC (Electro Magnetic Compatibility) performance and malfunctions throughout the system.

[0111] In the control board of the sixth aspect of the present disclosure, in any of the first to fifth aspects, the CPU may control the flow of current to each electronic expansion valve up to the number of pulses required for initialization to close all the electronic expansion valves to the fully closed position before controlling the electronic expansion valves to be controlled.

[0112] If initialization is performed when the electronic expansion valve is at a low opening, unnecessary force will be applied, shortening the life of the electronic expansion valve, but this can be prevented by the position adjustment of the present disclosure.

[0113] The control board of the seventh aspect of the present disclosure includes a CPU that controls a plurality of electronic expansion valves via a drive driver, a drive driver that is provided one-to-one with the CPU and configured to set the operation of the electronic expansion valve to be controlled via SPI communication from the CPU, and a changeover switch that switches the current path so that current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on an advanced phase clock signal output from the CPU.

[0114] While the CPU controls multiple electronic expansion valves via a drive driver, the control board includes input / output via SPI communication and a selector switch that switches the current path so that current flows from the drive driver to the electronic expansion valve to be controlled. This allows the control board to be equipped with the components necessary to control multiple electronic expansion valves, simplifying the wiring of the control board. By configuring operation via SPI communication, the number of components required for the circuit can be reduced, thereby reducing and saving the board area of ​​the control board. For example, adding one electronic expansion valve to the control board of the present disclosure requires only two selector switches and one CPU port for the drive driver to enable control.

[0115] An air conditioner according to an eighth aspect of the present disclosure may include a compressor, a condenser, an electronic expansion valve controlled by a control board according to any one of the first to seventh aspects, and an evaporator.

[0116] A control method of a ninth aspect of the present disclosure includes the steps of controlling a plurality of electronic expansion valves via a drive driver, switching the drive driver to a setting of the electronic expansion valve to be controlled in accordance with an operation setting switching signal output from a CPU so as to perform operation settings for the electronic expansion valve, and switching a current path so that current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on the advanced phase clock signal output from the CPU, and is executed by a computer.

[0117] A control program according to a tenth aspect of the present disclosure causes a computer to execute the control method according to the ninth aspect.

[0118] 1 Control board 10 (10a, 10b) Electronic expansion valve (expansion valve) 20 (20a, 20b) Drive driver 31, 32 Load (dummy load) 41, 42, 43, 44 Resistor 50 CPU 60 Operation setting switch 70 Changeover switch 80 Connector 90 ECU 100 HVAC ECU 520 Electric compressor 530 Water pump 540 Pressure sensor 550 Temperature sensor 560 Solenoid valve 1100 CPU 1200 Main memory device 1300 Secondary memory device 1400 Communication I / F (interface) 1500 Input / output unit 1800 Bus

Claims

1. A control board comprising: a CPU that controls a plurality of electronic expansion valves via a drive driver; the drive driver provided in a one-to-one correspondence with the CPU; an operation setting switch that switches the drive driver to a setting of the electronic expansion valve to be controlled in response to an operation setting switching signal output from the CPU so as to perform operation setting for the electronic expansion valve; and a changeover switch that switches a current path so that current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on the advanced phase clock signal output from the CPU.

2. The control board of claim 1, wherein the CPU calls up the stored electrical angle of the electronic expansion valve to be controlled, the changeover switch switches the current path so that a current flows from the drive driver to a load at a current value based on the phase-advance clock signal output from the CPU, and the drive driver increases or decreases the electrical angle by one step in accordance with the phase-advance clock signal until the electrical angle of the electronic expansion valve to be controlled matches the electrical angle of the drive driver.

3. The control board according to claim 1, wherein the CPU fixes the stop positions of the electronic expansion valves and ends the control.

4. The control board according to claim 1, wherein wiring for the positive or negative sides of each phase of the electronic expansion valve is shared outside the control board.

5. A control board according to claim 1, wherein wiring for the positive or negative sides of each phase of the electronic expansion valve is commonized within the control board.

6. The control board according to claim 1, wherein the CPU controls the flow of the current to each of the electronic expansion valves up to the number of pulses required for initialization to close all of the electronic expansion valves to a fully closed position before controlling the electronic expansion valve to be controlled.

7. A control board comprising: a CPU that controls a plurality of electronic expansion valves via a drive driver; a drive driver that is provided one-to-one with the CPU and configured to set the operation of the electronic expansion valve to be controlled by the CPU via SPI communication; and a change-over switch that switches a current path so that a current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on an advanced phase clock signal output from the CPU.

8. An air conditioner comprising: a compressor; a condenser; an electronic expansion valve controlled by the control board according to claim 1; and an evaporator.

9. A control method executed by a computer, comprising: a step of controlling a plurality of electronic expansion valves via a drive driver; a step of switching the drive driver to a setting of the electronic expansion valve to be controlled in response to an operation setting switching signal output from a CPU, so as to perform operation setting for the electronic expansion valve to be controlled; and a step of switching a current path so that a current flows from the drive driver to the electronic expansion valve to be controlled at a current value based on the advanced phase clock signal output from the CPU.

10. A control program for causing a computer to execute the control method according to claim 9.

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